臭氧尾气回用对曝气池污泥影响研究

将活性污泥分别在14.68、30.72、43.84 mg/L 3种臭氧浓度下进行氧化,同时以纯氧曝气作为平行实验,考察臭氧尾气对活性污泥的影响。结果表明,污泥经纯氧曝气后,在反应时间内并无明显变化,但在臭氧氧化过程中,污泥ATP下降,同时上清液中COD、TP、TN上升,且臭氧浓度越高,变化速率越大,其原因为污泥发生了溶胞现象;臭氧氧化后,污泥MLSS、MLVSS减少,污泥呼吸速率下降,但沉降性得到改善,同样随着臭氧浓度的升高,变化更为显著。经14.68、30.72 mg/L臭氧氧化后的污泥,其硝化能力、生化能力与反应前并无明显差距,而经43.84 mg/L臭氧氧化后污泥的硝化能力、生化能力明显弱于反应前。

Research on the influences of ozone off-gas recycling on aeration tank sludge

Activated sludge is oxidized when the ozone concentrations are 14.68 mg/L,30.72 mg/L and 43.84 mg/L, respectively. Meanwhile,pure oxygen aeration is used in the parallel experiment for investigating the influence of ozone off-gas on activated sludge. The results show that no obvious changes are observed in the reaction time ,after the sludge has been aerated with pure oxygen. But during ozonation process,adenosine triphosphate(ATP) of sludge decreases with the increase of chemical oxygen demand (COD),total phosphorous (TP) and total nitrogen (TN) of supernatant. The higher the ozone concentration is ,the faster the variation rates are ,which might be explained by sludge cell lysis. After ozonation,mixed liquor suspended solids(MLSS) and mixed liquor volatile suspended solids (MLVSS) decrease,and oxygen uptake rate (OUR) declines,but the settlement ability has been improved. In the same way,with the increase of ozone concentration,the changes are more obvious. After the ozonation process in which ozone concentrations are 14.68 mg/L and 30.72 mg/L ,the sludge nitrification ability and biodegradation ability do not have obvious changes,compared with the abilities before the reaction. After the ozonation process in which ozone concentration is 43.84 mg/L ,the sludge nitrification ability and biodegradation ability are obviously weak,compared with the abilities before the reaction.